Abstract

1,196,522. Inductive signalling. DICTAPHONE CORP. 30 Jan., 1968 [31 Jan., J967]. No. 4829/68. Heading H4U. In an inductive signalling system a further loop is inductively coupled to the transmitting loop to develop a negative feedback voltage which is fed back to an input of the transmitter to improve the linearity of the system. As shown, audio signals from a tape recorder 12 are amplified at 14 and supplied via transmitting loop 16 to the inductively coupled receivers 20a &c. A second loop 18 adjacent the loop 16 develops negative feedback signals which are applied to the input of the amplifier 14. The system also reduces the effect of interfering signals.